Being overweight or obese means that excess fat is causing health problems.

    It is most commonly measured by Body Mass Index (BMI). Your BMI is your weight (kg) divided by the square (number multiplied by itself) of your height in meters.

    Find your BMI

    Work out your height in metres and multiply the figure by itself.

    Measure your weight in kilograms.

    Divide the weight by the height squared (ie, the answer to question 1). For example, you might be 1.6m (5ft 3in) tall and weigh 65kg (10st).

    The calculation would then be:

    65 / 1.6x1.6 = 24.52

    WHO BMI classification

    Normal BMI between 18.5 and 24.99

    Overweight with a BMI >25

    Obese with a BMI >30

    Note, that with a BMI higher than 21 the risk of chronic disease increases.

    超重或肥胖指过度肥胖正导致健康问题。

    通常采用体重指数（BMI）来衡量。你的BMI指数是你的体重（公斤）除以你身高（米）的平方（身高乘身高）。

    计算你的BMI指数

    测量你的身高，以米为单位，并将数字相乘。

    测量你的体重，以公斤为单位。

    用身高的平方（也就是问题一的答案）除以体重。例如，你可能高1.6米（5英尺3英寸），重65公斤。

    算式即为：

    65 / 1.6x1.6 = 24.52

    世界卫生组织BMI指数分级

    正常BMI指数 18.5至24.99

    超重BMI指数大于25

    肥胖BMI指数大于30

    注意，BMI指数高出正常21个点的罹患慢性疾病的风险也将上升。